Equipment has been available for sometime for the stacking of corrugated cardboard sheets, such as supplied by a cutting machine, referred to in the trade as a "corrugator". Such equipment is generally constructed to convey the corrugated sheets to a stacking station where the sheets are stacked in superposed relation. When the stack reaches a predetermined height, it is transferred by any suitable means to another location, such as for shipment to a purchaser or to a box cutting machine in the same plant. Such stacking equipment generally includes an abutment stop mechanism by which the sheet flow is stopped for the interval of time during which the completed stack is removed from the stacking station and the station is readied to receive the first of another stack of sheets. The interruption in the supply of sheets to the stacker, of course, results in a backup on the feed conveyor leading to the stop mechanism, such pile ups usually tend to be unstable, particularly with high speed equipment and when the sheets are relatively large and bulky. Not infrequently, backup of large corrugated fiber board sheets will become unstable and skew or shift on the conveyor so that upon the release by the abutment stop mechanism and resumption of the feed cycle, the sheets which make up the pile will become misaligned and cause improper stacking, the result being that shut-downs for operator corrective action have all too frequently been required.
The principal object of this invention is to provide a high speed feeding and stacking mechanism for corrugated sheets which is capable of efficiently stacking without the drawbacks of the equipment heretofore available.